Multiple system atrophy (MSA) and Parkinson's disease (PD) are synucleinopathies characterized by aggregation of α-synuclein in brain cells. Recent studies have shown that morphological changes in terms of cerebral nerve cell loss and increase in glia cell numbers, the degree of brain atrophy and molecular and epidemiological findings are more severe in MSA than PD. In the present study, we performed a stereological comparison of cerebellar volumes, granule and Purkinje cells in 13 patients diagnosed with MSA [8 MSA-P (striatonigral subtype) and 5 MSA-C (olivopontocerebellar subtype)], 12 PD patients, and 15 age-matched control subjects. Only brains from MSA-C patients showed a reduction in the total number of Purkinje cells (anterior lobe) whereas both MSA-P and MSA-C patients had reduced Purkinje cell volumes (perikaryons and nuclei volume). The cerebellum of both diseases showed a reduction in the white matter volume compared to controls. The number of granule cells was unaffected in both diseases. Analyses of cell type-specific mRNA expression supported our structural data. This study of the cerebellum is in line with previous findings in the cerebrum and demonstrates that the degree of morphological changes is more pronounced in MSA-C than MSA-P and PD. Further, our results support an explicit involvement of cerebellar Purkinje cells and white matter connectivity in MSA-C > MSA-P and points to the potential importance of white matter alterations in PD pathology.

中文翻译：

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多系统萎缩和帕金森病患者小脑的病理变化——体视学研究。

多系统萎缩 (MSA) 和帕金森病 (PD) 是突触核蛋白病，其特征是脑细胞中 α-突触核蛋白聚集。最近的研究表明，MSA 中脑神经细胞丢失、胶质细胞数量增加、脑萎缩程度以及分子和流行病学发现等形态学变化比 PD 更为严重。在本研究中，我们对 13 名诊断为 MSA 的患者 [8 名 MSA-P（纹状体黑质亚型）和 5 名 MSA-C（橄榄脑桥小脑亚型）]、12 名 PD 患者和 15 名 MSA 患者的小脑体积、颗粒和浦肯野细胞进行了体视学比较。年龄匹配的对照对象。仅 MSA-C 患者的大脑显示浦肯野细胞（前叶）总数减少，而 MSA-P 和 MSA-C 患者的浦肯野细胞体积（核周和细胞核体积）均减少。与对照组相比，两种疾病的小脑白质体积均减少。两种疾病中颗粒细胞的数量均不受影响。细胞类型特异性 mRNA 表达的分析支持了我们的结构数据。这项小脑研究与之前的大脑研究结果一致，表明 MSA-C 中的形态变化程度比 MSA-P 和 PD 中更明显。此外，我们的结果支持小脑浦肯野细胞和白质连接在 MSA-C > MSA-P 中的明确参与，并指出白质改变在 PD 病理学中的潜在重要性。